Sailboat rigging

ABSTRACT

A sailboat in which a vertical mast is pivotally mounted upon the hull for free swinging movement about a vertical axis of rotation located aft of the mast and toward the center of the sailboat to maintain the distance between the center of effort of the sail and the axis of rotation small and to maintain the horizontal distance between the center of effort and the center of the sailboat small and relatively unchanged regardless of the orientation of the sail. In a gaff-rigged sailboat, the boom and the gaff are fixed against rotation upon the mast so that the mast is subjected to torsion between the boom and the gaff and resiliently biases the gaff and the boom into a common plane.

United States Patent Kratz 1 Apr. 18, 1972 I54} SAILBOAT RIGGING [72] Inventor: Kenneth E. Kratz, P.O. Box 356, West- Primary Examiner-Trygve M. Blix Attorney-Samuelson 8: Jacob [57] ABSTRACT A sailboat in which a vertical mast is pivotally mounted upon the hull for free swinging movement about a vertical axis of rotation located aft of the mast and toward the center of the sailboat to maintain the distance between the center of effort of the sail and the axis of rotation small and to maintain the horizontal distance between the center of efiort and the center of the sailboat small and relatively unchanged regardless of the orientation of the sail. In a gaff-rigged sailboat, the boom and the gaff are fixed against rotation upon the mast so that the mast is subjected to torsion between the boom and the gaff and resiliently biases the gaff and the boom into a common plane.

15 Claims, 5 Drawing Figures PATENTEDAPR 1 8 I972 SHEET 1 BF 2 INVENTOR. KENNETH E. KRATZ mtmmw m2 SHEET 2 0F 2 INVENTOR. KENNETH E. KRATZ SAILBOAT IRIGGING The present invention relates generally to sailboats and pertains, more specifically, to improvements in the rigging of sailboats.

Currently, boating is enjoying increased popularity as more people become interested in piloting their own boats. The demand for small boats, in particular, as become great and has given rise to the requirement for boats which are easier to operate and which will operate with greater safety than before. These requirements are especially important in small sailboats which require some degree of skill for their proper operation and which are more apt to be operated by persons having little skill in the handling of such sailboats.

It is therefore an important object of the invention to provide sailboats with improved rigging for the purpose of increasing the ease of handling such sailboats.

Another object of the invention is to provide sailboats with rigging which enables simple operation with increased safety.

Still another object of the invention is to provide a sailboat with rigging which establishes better balance and control together with more efficient propulsion.

A further object of the invention is to provide, in a gaffrigged sailboat, a flatter, more efficient sail.

A still further object of the invention is to provide, in a gaffrigged sailboat, rigging which enables better balance and increased ease of control, with more efficient propulsion.

The above objects, as well as still further objects and advantages, are attained by the invention which may be described briefly as providing in a sailing boat having a hull and a sail supported on the hull by a mast and a boom, the boom having opposite ends and being coupled to the mast adjacent one of the opposite ends such that the mast and the boom lie in a common plane, means precluding movement of the boom relative to the mast in directions transverse to the common plane, and means mounting the mast upon the hull for free rotation about an axis adjacent the center of effort of the sail, the axis being generally parallel to and spaced laterally from the mast in the direction extending from the mast toward the other of the opposite ends of the boom.

In addition, the invention contemplates, in a gaff-rigged sailboat, a gaff, means for affixing the gaff to the mast at a location spaced from the boom, and means for precluding movement of the gaff relative to the mast in directions transverse to the plane of the gaff and the mast at that location such that transverse movement of the gaff relative to the boom results in torsion of the mast between the boom and the gaff.

The invention will be more fully understood, while still further objects and advantages will be made apparent, by reference to the following detailed description of preferred embodiments of the invention illustrated in the accompanying drawing, in which:

Flg. l is a rear perspective view of a sailboat employing rigging constructed in accordance with the invention;

FIG. 2 is an enlarged fragmentary view of a portion of FIG.

FIG. 3 is a side elevational view of a sailboat employing alternate rigging constructed in accordance with the invention;

FIG. 4 is an enlarged cross-sectional view taken along line 4-4 of FIG. 3; and

FIG. 5 is a fragmentary elevational view illustrating a component part of the arrangement of FIG. 4.

Referring now to the drawing, and especially to FIGS. 1 and 2 thereof, a sailboat is illustrated generally at and is seen to have a hull 12 which includes a bow 14 and a stem 16. A rudder 18 is affixed to the stern in a conventional manner and includes a tiller 20 extending to a passenger compartment 22 which is surrounded by a coaming 24 and a deck 26.

The sail 28 of sailboat 10 is supported by a vertical mast 30 and a boom 32 which extends generally in a horizontal direction between opposite ends 34 and 36. The boom 32 is coupled to the mast 30 by means of a clevis 38 at end 34 of the boom. As best seen in FIG. 2, a pin 40 passes through the mast 30 and the clevis 38 is journaled upon the pin 40 such that the boom 32 and the mast lie in a common vertical plane and movement of the boom relative to the mast in directions transverse to the common vertical plane is precluded. However, the boom 32 is free to move within the common plane by pivoting about the longitudinal axis of the pin 40 which extends generally perpendicular to the common plane.

The mast 30 itself is affixed to one end of a horizontalbeam 42 and the other end of the beam 42 is affixed to the vertical shaft 44 journaled upon the hull 12 by means of upper and lower bearings 46 and 48, the vertical shaft 44 being retained against upward vertical movement by a retaining ring 50 engaged within an annular groove 52 in the shaft 44. In this manner, the mast 30 is free to rotate or swing about the longitudinal axis 54 of the shaft 44. The axis of rotation 54 of the shaft 44 is located at or near the center of the hull 1.2 and lies in the same common plane with the mast 30 and the boom 32. Thus, the axis of rotation 54 is parallel to the mast and is spaced laterally from the mast in the direction extending from the mast 30 toward the end 36 of the boom 32. Additionally, the axis of rotation 54 is located between the mast and the center of effort 56 of the sail 28, with the center of effort 56 located relatively close to the axis of rotation 54. The center of effort of the sail is that point at which the whole propelling force of the wind might be applied to the sail to produce the same effect as when distributed over the entire area of the sail.

Because the sail assembly, which includes the boom 32 and the mast 30, as well as the sail 28, is free to rotate about the axis of rotation 54, the wind may position the sail assembly to the best advantage. The proximity of the center of effort 56 and the axis of rotation 54 will keep the moment of the wind force about the axis of rotation at a minimum regardless of the orientation of the sail assembly. The combination of the free swinging sail assembly and the small moment of force about the axis of rotation results in a lesser tendency for the bull to point back into the wind with a concomitant reduction in rudder correction, a reduction in drag and an increase in efficiency. In addition, control of the sailboat is enhanced by requiring less manual force upon the sheet 58 which is connected to the end 36 of the boom. Furthermore, the boom 32 may still be pivoted upwardly or downwardly, as in a conventional sail assembly, for manual adjustment of the sail assembly and for manual lifting of the boom to pass overhead when the boom shifts from side to side of the sailboat.

The location of the axis of rotation 54 with respect to the sail assembly also assures that the center of gravity of the sail assembly does not move too far from the center of the hullas the sail assembly swings about the axis of rotation. Thus, the weight of the sail assembly is more favorably distributed regardless of the orientation of the sail assembly thereby minimizing the tendency for the sailboat to tilt in response to shifting of the sail assembly.

Turning now to FIGS. 3 through 5, another sailboat is illustrated generally at 60 and is seen to have an arrangement similar to sailboat 10 in that a sail 62 is carried upon a hull 64 by a vertical mast 66 and a boom 68 affixed to the mast by means of a clevis 70 and a pin 72, and the lower end of the mast 66 is affixed to one end of a horizontal beam 74, the other end of which is affixed to a vertical shaft 76 journaled in the hull 64 at or near the center of the hull. The axis of rotation 78 of the sail assembly is located near the center of effort 80 of the sail, as described above.

Sailboat 60, however, is gaff-rigged and includes a gaff 82 affixed to the mast 66 at a location 84, spaced vertically from the boom 68, by means of another clevis 86 which carries a pair of pins 88, each pin 88 engaging a slot 90 within a bracket 92 affixed to the mast 66 at the location 84. The gaff 82 may be selectively raised or lowered by a line 94, the pins 88 merely sliding into or out of their corresponding slots 90 to enable such raising or lowering of the gaff 82. A strap 96 bridges the otherwise open clevis 86 to retain the gaff 82 upon the mast 66 as the gaff is raised or lowered.

When the gaff 82 is raised and the pins 88 are seated within their respective slots 90, the gaff is precluded from moving relative to the mast 66 at location 84 in directions transverse to the vertical plane which contains the mast 66 and the boom 68, as well as the gaff 82, and any such movement in response to the force of the wind upon the sail 62 will result in torsion of the mast 66 between the boom 68 and the gaff 82. The mast 66 is so constructed as to permit a limited amount of torsion, thereby enabling limited horizontal movement of the gaff 82 relative to the boom 68 while resiliently biasing the gaff back into the vertical plane of the boom and the mast. In this manner, the sail is kept in a relatively more efficient configuration.

Since the entire sail assembly is free to rotate about the axis of rotation 78 the weight of the sail assembly will not shift over the side of the boat as is the case with ordinary gaff-rigged sails. Thus, the greater sail area available in a gaff-rigged sail is now made available in a relatively small sailboat without the disadvantage of poor weight distribution. Furthermore, the resilient bias of the mast in torsion can keep the sail in its most effective configuration without adversely affecting the attitude ofthe sailboat.

As seen in FIG. 3, the mast may be hinged at 98, if desired, to enable the mast to be folded and extend in a fore and aft direction for purposes of transporting the sailboat. When the sailboat is in use, the mast is latched in the erect position shown and the hinge 98 is ineffective.

It is to be understood that the above detailed description of preferred embodiments of the invention is provided by way of example only. Various details of design and construction may be modified without departing from the true spirit and scope ofthe invention as set forth in the appended claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

I. In a sailing boat having a hull and a sail supported on the hull by a mast and a boom, the boom having opposite ends and being coupled to the mast adjacent one of the opposite ends such that the mast and the boom lie in a common plane;

means precluding movement of the boom relative to the mast in directions transverse to the common plane; and

means mounting the mast upon the hull for free rotation about an axis located between the mast and the center of effort of the sail, said axis being generally parallel to and spaced laterally from the mast in the direction extending from the mast toward the other of the opposite ends of the boom.

2. The invention ofclaim 1 wherein the axis of rotation is in the common plane.

3. The invention of claim 2 wherein the axis of rotation is closer to the center of effort than to the mast.

4. The invention of claim 3 including means permitting pivotal movement of the boom relative to the mast within the common plane.

5. The invention ofclaim 1 including:

a gaff;

means for affixing the gaff to the mast at a location spaced from the boom; and

means for precluding movement of the gaff relative to the mast in directions transverse to the plane of the gaff and the mast at said location such that transverse movement of the gaff relative to the boom results in torsion of the mast between the boom and the gaff.

6. The invention ofclaim 5 wherein the plane ofthe gaff and the mast is said common plane.

7. The invention ofclaim I wherein:

the mast is vertical;

the boom is generally horizontal;

the common plane is a vertical plane;

the means mounting the mast upon the hull includes a horizontal beam having opposite ends, one of said ends being affixed to the mast, and

means journaling the other of said ends upon the hull for rotation of the beam about a vertical axis adjacent the center of the sailboat and between the mast and the center of effort of the sail; and means coupling the boom to the mast such that the boom extends through the vertical axis.

8. The invention of claim 7 wherein said coupling means includes a pivot which permits pivotal movement of the boom relative to the mast in the vertical plane while precluding pivotal movement of the boom relative to the mast in horizontal planes.

9. The invention of claim 8 wherein said pivot includes a pivot pin extending perpendicular to said vertical plane.

10. The invention ofclaim 7 including:

a gaff; and

a pivot coupling the gaff to the mast at a location above the boom such that the gaff and the boom lie in the same vertical plane, said pivot permitting pivotal movement of the gaff relative to the mast in the vertical plane while precluding pivotal movement of the gait relative to the mast at said location in horizontal planes such that horizontal movement of the gaff relative to the boom results in torsion of the mast between the boom and the gaff;

said mast, by virtue of said torsion, permitting horizontal movement of the gaff relative to the boom while resiliently biasing the gaff into said vertical plane.

11. The invention of claim 10 including means for selectively uncoupling the pivot which couples the gaff to the mast at said location above the boom.

12. In a sailing boat having a hull and a sail supported on the hull by a mast and a boom, the boom being coupled to the mast such that the mast and the boom lie in a common plane:

means precluding movement of the boom relative to the mast in directions transverse to the common plane;

means mounting the mast upon the hull for rotation about an axis extending in the same direction as the mast;

a gaff;

means for affixing the gaff to the mast at a location spaced from the boom; and

means for precluding movement of the gaff relative to the mast in directions transverse to the plane of the gaff and the mast at said location such that transverse movement of the gaff relative to the boom results in torsion of the mast between the boom and the gaff.

13. The invention of claim 12 wherein the plane of the gaff and the mast is said common plane.

14. The invention of claim 12 including:

a first pivot coupling the boom to the mast;

said first pivot permitting pivotal movement of the boom relative to the mast in the vertical plane while precluding pivotal movement of the boom relative to the mast in horizontal planes; and

a second pivot coupling the gaff to the mast at a location above the boom such that the gaff and the boom lie in the same vertical plane, said second pivot permitting pivotal movement of the gaff relative to the mast and the vertical plane while precluding pivotal movement of the gaff relative to the mast at said location in horizontal planes, such that horizontal movement of the gaff relative to the boom results in torsion of the mast between the boom and the gaff;

said mast, by virtue of said torsion, permitting limited horizontal movement of the gaff relative to the boom while resiliently biasing the gaff into said vertical plane.

15. The invention ofclaim 14 including means for selectively uncoupling the second pivot. 

1. In a sailing boat having a hull and a sail supported on the hull by a mast and a boom, the boom having opposite ends and being coupled to the mast adjacent one of the opposite ends such that the mast and the boom lie in a common plane; means precluding movement of the boom relative to the mast in directions transverse to the common plane; and means mounting the mast upon the hull for free rotation about an axis located between the mast and the center of effort of the sail, said axis being generally parAllel to and spaced laterally from the mast in the direction extending from the mast toward the other of the opposite ends of the boom.
 2. The invention of claim 1 wherein the axis of rotation is in the common plane.
 3. The invention of claim 2 wherein the axis of rotation is closer to the center of effort than to the mast.
 4. The invention of claim 3 including means permitting pivotal movement of the boom relative to the mast within the common plane.
 5. The invention of claim 1 including: a gaff; means for affixing the gaff to the mast at a location spaced from the boom; and means for precluding movement of the gaff relative to the mast in directions transverse to the plane of the gaff and the mast at said location such that transverse movement of the gaff relative to the boom results in torsion of the mast between the boom and the gaff.
 6. The invention of claim 5 wherein the plane of the gaff and the mast is said common plane.
 7. The invention of claim 1 wherein: the mast is vertical; the boom is generally horizontal; the common plane is a vertical plane; the means mounting the mast upon the hull includes a horizontal beam having opposite ends, one of said ends being affixed to the mast, and means journaling the other of said ends upon the hull for rotation of the beam about a vertical axis adjacent the center of the sailboat and between the mast and the center of effort of the sail; and means coupling the boom to the mast such that the boom extends through the vertical axis.
 8. The invention of claim 7 wherein said coupling means includes a pivot which permits pivotal movement of the boom relative to the mast in the vertical plane while precluding pivotal movement of the boom relative to the mast in horizontal planes.
 9. The invention of claim 8 wherein said pivot includes a pivot pin extending perpendicular to said vertical plane.
 10. The invention of claim 7 including: a gaff; and a pivot coupling the gaff to the mast at a location above the boom such that the gaff and the boom lie in the same vertical plane, said pivot permitting pivotal movement of the gaff relative to the mast in the vertical plane while precluding pivotal movement of the gaff relative to the mast at said location in horizontal planes such that horizontal movement of the gaff relative to the boom results in torsion of the mast between the boom and the gaff; said mast, by virtue of said torsion, permitting horizontal movement of the gaff relative to the boom while resiliently biasing the gaff into said vertical plane.
 11. The invention of claim 10 including means for selectively uncoupling the pivot which couples the gaff to the mast at said location above the boom.
 12. In a sailing boat having a hull and a sail supported on the hull by a mast and a boom, the boom being coupled to the mast such that the mast and the boom lie in a common plane: means precluding movement of the boom relative to the mast in directions transverse to the common plane; means mounting the mast upon the hull for rotation about an axis extending in the same direction as the mast; a gaff; means for affixing the gaff to the mast at a location spaced from the boom; and means for precluding movement of the gaff relative to the mast in directions transverse to the plane of the gaff and the mast at said location such that transverse movement of the gaff relative to the boom results in torsion of the mast between the boom and the gaff.
 13. The invention of claim 12 wherein the plane of the gaff and the mast is said common plane.
 14. The invention of claim 12 including: a first pivot coupling the boom to the mast; said first pivot permitting pivotal movement of the boom relative to the mast in the vertical plane while precluding pivotal movement of the boom relative to the mast in horizontal planes; and a second pivot coupling the gaff to the mast at a location above the boom such that the gafF and the boom lie in the same vertical plane, said second pivot permitting pivotal movement of the gaff relative to the mast and the vertical plane while precluding pivotal movement of the gaff relative to the mast at said location in horizontal planes, such that horizontal movement of the gaff relative to the boom results in torsion of the mast between the boom and the gaff; said mast, by virtue of said torsion, permitting limited horizontal movement of the gaff relative to the boom while resiliently biasing the gaff into said vertical plane.
 15. The invention of claim 14 including means for selectively uncoupling the second pivot. 